The present invention relates to automatic image analysis, and more particularly, to automatic object recognition in images and image sequences based on two-dimensional shape primatives. The invention is advantageous for image analysis and object recognition for complex scenes in which an object is presented in front of a structured background.
Typical automatic manufacturing controls and especially robot arm controls generally fail to provide adequate automatic adaptation to new materials introduced into an industrial process. Generally, any details and possible situations of the process must be regarded and implemented beforehand. To overcome such a precise constructions and to overcome the restriction to the number of materials for which the process has been constructed, materialsxe2x80x94or more generally speaking, objectsxe2x80x94must be treated in a sophisticated way. Accordingly, the representations of new objects must be created automatically so that they can be recognized at any place in the manufacturing process. Such an automation may also improve other kinds of applications, such as e.g. the automatic organization of a warehouse.
Existing algorithms (see, e.g., Martin Lades, Jan C. Vorbrxc3xcggen, Joachim Buhmann, Jxc3x6rg Lange, Christoph v.d. Malsburg, Rolf P. Wxc3xcrtz, and Wolfgang Konen, xe2x80x9cDistortion invariant object recognition in the dynamic link architecturexe2x80x9d, IEEE Trans. Comput., 42(3):300 311, 1993, and Laurenz Wiskott, Jean-Marc Fellous, Norbert Krxc3xciger, and Christoph von der Malsburg, xe2x80x9cFace recognition by elastic bunch graph matchingxe2x80x9d, IEEE-PA MI, 19(7):775-779, 1997) allow for automatic recognition of objects but have the following two drawbacks: first, such algorithms work most properly for objects containing much texture but less well for manmade objects, because these kind of objects mainly consist of edges and need a good description of their contour in most cases. Second, the representation is not created automatically, i.e., the locations within an image which shall be used for the representation have to be defined by hand.
Accordingly, there exists a definite need for automatic image analysis techniques that can automatically generate representations for new objects for recognition in a variety of industrial manufacturing processes and environments. The present invention satisfies these needs and provides further related advantages.
The invention provides an apparatus, and related method, for providing a procedure to analyze images based on two-dimensional shape primitives. In the procedure, an object representation is created automatically from an image and then this representation is applied to another image for the purpose of object recognition. The features used for the representation are the two types of two-dimensional shape primitives: local line segments and vertices. Furthermore, the creation of object representations is extended to sequences of images, which is especially needed for complex scenes in which, for example, the object is presented in front of a structured background.
Other features and advantages of the present invention should become apparent from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.